javax.microedition.lcdui
Class TextField

java.lang.Object
  javax.microedition.lcdui.Item
      javax.microedition.lcdui.TextField

public class TextField
extends Item

A TextField is an editable text component that may be placed into a Form. It can be given a piece of text that is used as the initial value.

A TextField has a maximum size, which is the maximum number of characters that can be stored in the object at any time (its capacity). This limit is enforced when the TextField instance is constructed, when the user is editing text within the TextField, as well as when the application program calls methods on the TextField that modify its contents. The maximum size is the maximum stored capacity and is unrelated to the number of characters that may be displayed at any given time. The number of characters displayed and their arrangement into rows and columns are determined by the device.

The implementation may place a boundary on the maximum size, and the maximum size actually assigned may be smaller than the application had requested. The value actually assigned will be reflected in the value returned by getMaxSize(). A defensively-written application should compare this value to the maximum size requested and be prepared to handle cases where they differ.

Input Constraints

The TextField shares the concept of input constraints with the TextBox class. The different constraints allow the application to request that the user's input be restricted in a variety of ways. The implementation is required to restrict the user's input as requested by the application. For example, if the application requests the NUMERIC constraint on a TextField, the implementation must allow only numeric characters to be entered.

The actual contents of the text object are set and modified by and are reported to the application through the TextBox and TextField APIs. The displayed contents may differ from the actual contents if the implementation has chosen to provide special formatting suitable for the text object's constraint setting. For example, a PHONENUMBER field might be displayed with digit separators and punctuation as appropriate for the phone number conventions in use, grouping the digits into country code, area code, prefix, etc. Any spaces or punctuation provided are not considered part of the text object's actual contents. For example, a text object with the PHONENUMBER constraint might display as follows:

 (408) 555-1212
 

but the actual contents of the object visible to the application through the APIs would be the string "4085551212". The size method reflects the number of characters in the actual contents, not the number of characters that are displayed, so for this example the size method would return 10.

Some constraints, such as DECIMAL, require the implementation to perform syntactic validation of the contents of the text object. The syntax checking is performed on the actual contents of the text object, which may differ from the displayed contents as described above. Syntax checking is performed on the initial contents passed to the constructors, and it is also enforced for all method calls that affect the contents of the text object. The methods and constructors throw IllegalArgumentException if they would result in the contents of the text object not conforming to the required syntax.

The value passed to the setConstraints() method consists of a restrictive constraint setting described above, as well as a variety of flag bits that modify the behavior of text entry and display. The value of the restrictive constraint setting is in the low order 16 bits of the value, and it may be extracted by combining the constraint value with the CONSTRAINT_MASK constant using the bit-wise AND (&) operator. The restrictive constraint settings are as follows:

ANY
EMAILADDR
NUMERIC
PHONENUMBER
URL
DECIMAL
CURRENCY


The modifier flags reside in the high order 16 bits of the constraint value, that is, those in the complement of the CONSTRAINT_MASK constant. The modifier flags may be tested individually by combining the constraint value with a modifier flag using the bit-wise AND (&) operator. The modifier flags are as follows:

PASSWORD
UNEDITABLE
SENSITIVE
NON_PREDICTIVE
INITIAL_CAPS_WORD
INITIAL_CAPS_SENTENCE


TextBox and TextField with input constraint TextField.ANY MUST support the input of at least the following set of characters:

Minimum set of characters supported by TextBox and TextField

Unicode value	Character name	Glyph
U+0020	SPACE	
U+0021	EXCLAMATION MARK	!
U+0022	QUOTATION MARK	
U+0023	NUMBER SIGN	#
U+0024	DOLLAR SIGN	$
U+0025	PERCENT SIGN	%
U+0026	AMPERSAND	&
U+0027	APOSTROPHE	'
U+0028	LEFT PARENTHESIS	(
U+0029	RIGHT PARENTHESIS	)
U+002A	ASTERISK	*
U+002B	PLUS SIGN	+
U+002C	COMMA	,
U+002D	HYPHEN-MINUS	-
U+002E	FULL STOP (period)	.
U+002F	SOLIDUS (slash)	/
U+0030...U+0039	DIGIT ZERO through DIGIT NINE	0...9
U+003A	COLON	:
U+003B	SEMICOLON	;
U+003C	LESS-THAN SIGN	<
U+003D	EQUALS SIGN	=
U+003E	GREATER-THAN SIGN	>
U+003F	QUESTION MARK	?
U+0040	COMMERCIAL AT	@
U+0041...U+005A	LATIN CAPITAL LETTER A through LATIN CAPITAL LETTER Z	A...Z
U+005B	LEFT SQUARE BRACKET	[
U+005C	REVERSE SOLIDUS (backslash)	\
U+005D	RIGHT SQUARE BRACKET	]
U+005E	CIRCUMFLEX ACCENT	^
U+005F	LOW LINE (underscore)	_
U+0060	GRAVE ACCENT	<
U+0061...U+007A	LATIN SMALL LETTER A through LATIN SMALL LETTER Z	a...z
U+007B	LEFT CURLY BRACKET	{
U+007C	VERTICAL LINE	|
U+007D	RIGHT CURLY BRACKET	}
U+007E	TILDE	~
U+00A1	INVERTED EXCLAMATION MARK	¡
U+00A3	POUND SIGN	£
U+00A4	CURRENCY SIGN	¤
U+00A5	YEN SIGN	¥
U+00A7	SECTION SIGN	§
U+00BF	INVERTED QUESTION MARK	¿
U+20AC	EURO SIGN	€
U+00A2	CENT SIGN	¢
U+00A8	DIAERESIS	¨
U+00A9	COPYRIGHT SIGN	©
U+00B0	DEGREE SIGN	°
U+00B4	ACUTE ACCENT	´
U+00B6	PILCROW SIGN	¶
U+00B7	MIDDLE DOT	·
U+000A	LINE FEED

Generally, any character that can be input using the input methods of the device SHOULD be supported.

Instances of TextField and TextBox with either of the constraints TextField.EMAILADDR and TextField.URL SHOULD allow the same characters to be input as are allowed for input constraint TextField.ANY. This is important particularly for entering URLs that are effectively IRIs (Internationalized Resource Identifiers, see [RFC3987]), which contain characters that would not traditionally be allowed in URLs. It is the responsibility of the application or the networking subsystem to encode the URLs into a format suitable for resource retrieval (using the mechanisms outlined in [RFC3987]).

Input Modes

The TextField shares the concept of input modes with the TextBox class. The application can request that the implementation use a particular input mode when the user initiates editing of a TextField or TextBox. The input mode is a concept that exists within the user interface for text entry on a particular device. The application does not request an input mode directly, since the user interface for text entry is not standardized across devices. Instead, the application can request that the entry of certain characters be made convenient. It can do this by passing the name of a Unicode character subset to the setInitialInputMode() method. Calling this method requests that the implementation set the mode of the text entry user interface so that it is convenient for the user to enter characters in this subset. The application can also request that the input mode have certain behavioral characteristics by setting modifier flags in the constraints value.

The requested input mode should be used whenever the user initiates the editing of a TextBox or TextField object. If the user had changed input modes in a previous editing session, the application's requested input mode should take precedence over the previous input mode set by the user. However, the input mode is not restrictive, and the user is allowed to change the input mode at any time during editing. If editing is already in progress, calls to the setInitialInputMode method do not affect the current input mode, but instead take effect at the next time the user initiates editing of this text object.

The initial input mode is a hint to the implementation. If the implementation cannot provide an input mode that satisfies the application's request, it should use a default input mode.

The input mode that results from the application's request is not a restriction on the set of characters the user is allowed to enter. The user MUST be allowed to switch input modes to enter any character that is allowed within the current constraint setting. The constraint setting takes precedence over an input mode request, and the implementation may refuse to supply a particular input mode if it is inconsistent with the current constraint setting.

For example, if the current constraint is ANY, the call

 setInitialInputMode("MIDP_UPPERCASE_LATIN");
 

should set the initial input mode to allow entry of uppercase Latin characters. This does not restrict input to these characters, and the user will be able to enter other characters by switching the input mode to allow entry of numerals or lowercase Latin letters. However, if the current constraint is NUMERIC, the implementation may ignore the request to set an initial input mode allowing MIDP_UPPERCASE_LATIN characters because these characters are not allowed in a TextField whose constraint is NUMERIC. In this case, the implementation may instead use an input mode that allows entry of numerals, since such an input mode is most appropriate for entry of data under the NUMERIC constraint.

A string is used to name the Unicode character subset passed as a parameter to the setInitialInputMode() method. String comparison is case sensitive.

Unicode character blocks can be named by adding the prefix "UCB_" to the string names of fields representing Unicode character blocks as defined in the J2SE class java.lang.Character.UnicodeBlock. Any Unicode character block may be named in this fashion. For convenience, the most common Unicode character blocks are listed below.

UCB_BASIC_LATIN
UCB_GREEK
UCB_CYRILLIC
UCB_ARMENIAN
UCB_HEBREW
UCB_ARABIC
UCB_DEVANAGARI
UCB_BENGALI
UCB_THAI
UCB_HIRAGANA
UCB_KATAKANA
UCB_HANGUL_SYLLABLES


"Input subsets" as defined by the J2SE class java.awt.im.InputSubset may be named by adding the prefix "IS_" to the string names of fields representing input subsets as defined in that class. Any defined input subset may be used. For convenience, the names of the currently defined input subsets are listed below.

IS_FULLWIDTH_DIGITS
IS_FULLWIDTH_LATIN
IS_HALFWIDTH_KATAKANA
IS_HANJA
IS_KANJI
IS_LATIN
IS_LATIN_DIGITS
IS_SIMPLIFIED_HANZI
IS_TRADITIONAL_HANZI


MIDP has also defined the following character subsets:

MIDP_UPPERCASE_LATIN - the subset of IS_LATIN that corresponds to uppercase Latin letters

MIDP_LOWERCASE_LATIN - the subset of IS_LATIN that corresponds to lowercase Latin letters

Finally, implementation-specific character subsets may be named with strings that have a prefix of "X_". In order to avoid namespace conflicts, it is recommended that implementation-specific names include the name of the defining company or organization after the initial "X_" prefix.

For example, a Japanese language application might have a particular TextField that the application intends to be used primarily for input of words that are "loaned" from languages other than Japanese. The application might request an input mode facilitating Hiragana input by issuing the following method call:

 textfield.setInitialInputMode("UCB_HIRAGANA");
 

Implementation Note

Implementations need not compile in all the strings listed above. Instead, they need only to compile in the strings that name Unicode character subsets that they support. If the subset name passed by the application does not match a known subset name, the request should simply be ignored without error, and a default input mode should be used. This lets implementations support this feature reasonably inexpensively. However, it has the consequence that the application cannot tell whether its request has been accepted, nor whether the Unicode character subset it has requested is actually a valid subset.

Since:

MIDP 1.0

Field Summary

static int	ANY The user is allowed to enter any text.
static int	CONSTRAINT_MASK The mask value for determining the constraint mode.
static int	CURRENCY The user is allowed to enter values that correspond to a currency amount.
static int	DECIMAL The user is allowed to enter numeric values with optional decimal fractions, for example "-123", "0.123", or ".5".
static int	EMAILADDR The user is allowed to enter an e-mail address.
static int	INITIAL_CAPS_SENTENCE This flag is a hint to the implementation that during text editing, the initial letter of each sentence should be capitalized.
static int	INITIAL_CAPS_WORD This flag is a hint to the implementation that during text editing, the initial letter of each word should be capitalized.
static int	NON_PREDICTIVE Indicates that the text entered does not consist of words that are likely to be found in dictionaries typically used by predictive input schemes.
static int	NUMERIC The user is allowed to enter only an integer value.
static int	PASSWORD Indicates that the text entered is confidential data that should be obscured whenever possible.
static int	PHONENUMBER The user is allowed to enter a phone number.
static int	SENSITIVE Indicates that the text entered is sensitive data that the implementation must never store into a dictionary or table for use in predictive, auto-completing, or other accelerated input schemes.
static int	UNEDITABLE Indicates that editing is currently disallowed.
static int	URL The user is allowed to enter a URL.

Fields inherited from class javax.microedition.lcdui.Item

BUTTON, HYPERLINK, LAYOUT_2, LAYOUT_BOTTOM, LAYOUT_CENTER, LAYOUT_DEFAULT, LAYOUT_EXPAND, LAYOUT_LEFT, LAYOUT_NEWLINE_AFTER, LAYOUT_NEWLINE_BEFORE, LAYOUT_RIGHT, LAYOUT_SHRINK, LAYOUT_TOP, LAYOUT_VCENTER, LAYOUT_VEXPAND, LAYOUT_VSHRINK, PLAIN

Constructor Summary

TextField(java.lang.String label, java.lang.String text, int maxSize, int constraints)
Creates a new TextField object with the given label, initial contents, maximum size in characters, and constraints.

Method Summary

void	delete(int offset, int length) Deletes characters from the TextField.
int	getCaretPosition() Gets the current input position.
int	getChars(char[] data) Copies the contents of the TextField into a character array starting at index zero.
int	getConstraints() Gets the current input constraints of the TextField.
int	getMaxSize() Returns the maximum size (number of characters) that can be stored in this TextField.
java.lang.String	getString() Gets the contents of the TextField as a string value.
void	insert(char[] data, int offset, int length, int position) Inserts a subrange of an array of characters into the contents of the TextField.
void	insert(java.lang.String src, int position) Inserts a string into the contents of the TextField.
void	setCaret(int index) Sets the index of the caret.
void	setChars(char[] data, int offset, int length) Sets the contents of the TextField from a character array, replacing the previous contents.
void	setConstraints(int constraints) Sets the input constraints of the TextField.
void	setHighlight(int index, int length) Sets the highlight on a range in the text.
void	setInitialInputMode(java.lang.String characterSubset) Sets a hint to the implementation as to the input mode that should be used when the user initiates editing of this TextField.
int	setMaxSize(int maxSize) Sets the maximum size (number of characters) that can be contained in this TextField.
void	setString(java.lang.String text) Sets the contents of the TextField as a string value, replacing the previous contents.
int	size() Gets the number of characters that are currently stored in this TextField.

Methods inherited from class javax.microedition.lcdui.Item

addCommand, getCommands, getLabel, getLayout, getLayoutHint, getMinimumHeight, getMinimumWidth, getPreferredHeight, getPreferredWidth, notifyStateChanged, removeCommand, setCommand, setDefaultCommand, setItemCommandListener, setLabel, setLayout, setLayoutHint, setPreferredSize

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ANY

public static final int ANY

The user is allowed to enter any text. Line breaks may be entered.

Constant 0 is assigned to ANY.

See Also:

Constant Field Values

EMAILADDR

public static final int EMAILADDR

The user is allowed to enter an e-mail address.

Constant 1 is assigned to EMAILADDR.

See Also:

Constant Field Values

NUMERIC

public static final int NUMERIC

The user is allowed to enter only an integer value. The implementation must restrict the contents either to be empty or to consist of an optional minus sign followed by a string of one or more decimal numerals. Unless the value is empty, it will be successfully parsable using Integer.parseInt(String).

The minus sign consumes space in the text object. It is thus impossible to enter negative numbers into a text object whose maximum size is 1.

The implementation MAY present the field with device-specific characters as part of a numeric string, such as spaces or commas for grouping separators. However, the only characters allowed in the actual contents of the text object are the optional minus sign and the numeric digits.

Constant 2 is assigned to NUMERIC.

See Also:

Constant Field Values

PHONENUMBER

public static final int PHONENUMBER

The user is allowed to enter a phone number. The phone number is a special case, since a phone-based implementation may be linked to the native phone dialing application. The implementation MAY automatically start a phone dialer application that is initialized so that pressing a single key would be enough to make a call. The call MUST NOT be made automatically without requiring user's confirmation. Implementations MAY also provide a feature to look up the phone number in the device's phone or address database.

The exact set of characters allowed is specific to the device and to the device's network, but typically includes non-numeric characters, such as a "+" prefix character. At least numeric digits, the plus sign, star and hash MUST be supported. The input of other characters SHOULD be allowed. Any character MAY be ignored by the implementation.

Implementations MAY provide the capability to initiate voice calls using the MIDlet.platformRequest method.

Constant 3 is assigned to PHONENUMBER.

See Also:

Constant Field Values

URL

public static final int URL

The user is allowed to enter a URL.

Constant 4 is assigned to URL.

See Also:

Constant Field Values

DECIMAL

public static final int DECIMAL

The user is allowed to enter numeric values with optional decimal fractions, for example "-123", "0.123", or ".5".

The implementation may display a period "." or a comma "," for the decimal fraction separator, depending on the conventions in use on the device. Similarly, the implementation may display other device-specific characters as part of a decimal string, such as spaces or commas for digit separators. However, the only characters allowed in the actual contents of the text object are period ".", minus sign "-", and the decimal digits.

The actual contents of a DECIMAL text object may be empty. If the actual contents are not empty, they must conform to a subset of the syntax for a FloatingPointLiteral as defined by the Java Language Specification [JLS], Section 3.10.2. This subset syntax is defined as follows: the actual contents must consist of an optional minus sign "-", followed by one or more whole-number decimal digits, followed by an optional fraction separator, followed by zero or more decimal fraction digits. The whole-number decimal digits may be omitted if the fraction separator and one or more decimal fraction digits are present.

The syntax defined above is also enforced whenever the application attempts to set or modify the contents of the text object by calling a constructor or a method.

Parsing this string value into a numeric value suitable for computation is the responsibility of the application. If the contents are not empty, the result can be parsed successfully by Double.valueOf and related methods if they are present in the runtime environment.

The implementation MAY present the field with device-specific characters as part of a numeric string, such as spaces or commas for grouping separators. However, the only characters allowed in the actual contents of the text object are the optional minus sign, the fraction separator and the numeric digits.

The sign and separators consume space in the text object. Applications SHOULD account for this when assigning a maximum size for the text object.

Constant 5 is assigned to DECIMAL.

Since:

MIDP 2.0

See Also:

Constant Field Values

CURRENCY

public static final int CURRENCY

The user is allowed to enter values that correspond to a currency amount. The format of the amount is the same as with the DECIMAL constant, but the implementation SHOULD present the number as an amount in the currency attached to the locale of the device, as determined by the microedition.locale system property.

Information about the currency symbol and its position in relation to the number SHOULD be retrieved from the Common Locale Data Repository (CLDR, see http://unicode.org/cldr/).

Examples of currency amount presentations for the number "12345.67" include:

Locale	Presentation
fi-FI	12 345,67 €
en-US	$12,345.67
en-GB	£12,345.67
ja-JP	¥ 12,345.67

The implementation MAY defer the presentation until the focus leaves the input field.

Constant 6 is assigned to CURRENCY.

Since:

MIDP 3.0

See Also:

Constant Field Values

PASSWORD

public static final int PASSWORD

Indicates that the text entered is confidential data that should be obscured whenever possible. The contents may be visible while the user is entering data. However, the contents must never be divulged to the user. In particular, the existing contents must not be shown when the user edits the contents. The means by which the contents are obscured is implementation-dependent. For example, each character of the data might be masked with a "*" character. The PASSWORD modifier is useful for entering confidential information such as passwords or personal identification numbers (PINs).

Data entered into a PASSWORD field is treated similarly to SENSITIVE in that the implementation must never store the contents into a dictionary or table for use in predictive, auto-completing, or other accelerated input schemes. If the PASSWORD bit is set in a constraint value, the SENSITIVE and NON_PREDICTIVE bits are also considered to be set, regardless of their actual values. In addition, the INITIAL_CAPS_WORD and INITIAL_CAPS_SENTENCE flag bits should be ignored even if they are set.

The PASSWORD modifier can be combined with other input constraints by using the bit-wise OR operator (|). The PASSWORD modifier is not useful with some constraint values such as EMAILADDR, PHONENUMBER, and URL. These combinations are legal, however, and no exception is thrown if such a constraint is specified.

Constant 0x10000 is assigned to PASSWORD.

See Also:

Constant Field Values

UNEDITABLE

public static final int UNEDITABLE

Indicates that editing is currently disallowed. When this flag is set, the implementation must prevent the user from changing the text contents of this object. The implementation should also provide a visual indication that the object's text cannot be edited. The intent of this flag is that this text object has the potential to be edited, and that there are circumstances where the application will clear this flag and allow the user to edit the contents.

The UNEDITABLE modifier can be combined with other input constraints by using the bit-wise OR operator (|).

Constant 0x20000 is assigned to UNEDITABLE.

Since:

MIDP 2.0

See Also:

Constant Field Values

SENSITIVE

public static final int SENSITIVE

Indicates that the text entered is sensitive data that the implementation must never store into a dictionary or table for use in predictive, auto-completing, or other accelerated input schemes. A credit card number is an example of sensitive data.

The SENSITIVE modifier can be combined with other input constraints by using the bit-wise OR operator (|).

Constant 0x40000 is assigned to SENSITIVE.

Since:

MIDP 2.0

See Also:

Constant Field Values

NON_PREDICTIVE

public static final int NON_PREDICTIVE

Indicates that the text entered does not consist of words that are likely to be found in dictionaries typically used by predictive input schemes. If this bit is clear, the implementation is allowed to (but is not required to) use predictive input facilities. If this bit is set, the implementation should not use any predictive input facilities, but it instead should allow character-by-character text entry.

The NON_PREDICTIVE modifier can be combined with other input constraints by using the bit-wise OR operator (|).

Constant 0x80000 is assigned to NON_PREDICTIVE.

Since:

MIDP 2.0

See Also:

Constant Field Values

INITIAL_CAPS_WORD

public static final int INITIAL_CAPS_WORD

This flag is a hint to the implementation that during text editing, the initial letter of each word should be capitalized. This hint should be honored only on devices for which automatic capitalization is appropriate and when the character set of the text being edited has the notion of upper case and lower case letters. The definition of word boundaries is implementation-specific.

If the application specifies both the INITIAL_CAPS_WORD and the INITIAL_CAPS_SENTENCE flags, INITIAL_CAPS_WORD behavior should be used.

The INITIAL_CAPS_WORD modifier can be combined with other input constraints by using the bit-wise OR operator (|).

Constant 0x100000 is assigned to INITIAL_CAPS_WORD.

Since:

MIDP 2.0

See Also:

Constant Field Values

INITIAL_CAPS_SENTENCE

public static final int INITIAL_CAPS_SENTENCE

This flag is a hint to the implementation that during text editing, the initial letter of each sentence should be capitalized. This hint should be honored only on devices for which automatic capitalization is appropriate and when the character set of the text being edited has the notion of upper case and lower case letters. The definition of sentence boundaries is implementation-specific.

If the application specifies both the INITIAL_CAPS_WORD and the INITIAL_CAPS_SENTENCE flags, INITIAL_CAPS_WORD behavior should be used.

The INITIAL_CAPS_SENTENCE modifier can be combined with other input constraints by using the bit-wise OR operator (|).

Constant 0x200000 is assigned to INITIAL_CAPS_SENTENCE.

Since:

MIDP 2.0

See Also:

Constant Field Values

CONSTRAINT_MASK

public static final int CONSTRAINT_MASK

The mask value for determining the constraint mode. The application should use the bit-wise AND operation with a value returned by getConstraints() and CONSTRAINT_MASK in order to retrieve the current constraint mode, in order to remove any modifier flags such as the PASSWORD flag.

Constant 0xFFFF is assigned to CONSTRAINT_MASK.

See Also:

Constant Field Values

Constructor Detail

TextField

public TextField(java.lang.String label,
                 java.lang.String text,
                 int maxSize,
                 int constraints)

Creates a new TextField object with the given label, initial contents, maximum size in characters, and constraints. If the text parameter is null, the TextField is created empty. The maxSize parameter must be greater than zero. An IllegalArgumentException is thrown if the length of the initial contents string exceeds maxSize. However, the implementation may assign a maximum size smaller than the application had requested. If this occurs, and if the length of the contents exceeds the newly assigned maximum size, the contents are truncated from the end in order to fit, and no exception is thrown.

Parameters:

label - item label

text - the initial contents, or null if the TextField is to be empty

maxSize - the maximum capacity in characters

constraints - see input constraints

Throws:

java.lang.IllegalArgumentException - if maxSize is zero or less

java.lang.IllegalArgumentException - if the value of the constraints parameter is invalid

java.lang.IllegalArgumentException - if text is illegal for the specified constraints

java.lang.IllegalArgumentException - if the length of the string exceeds the requested maximum capacity

Method Detail

getString

public java.lang.String getString()

Gets the contents of the TextField as a string value.

Returns:

the current contents

See Also:

setString(java.lang.String)

setString

public void setString(java.lang.String text)

Sets the contents of the TextField as a string value, replacing the previous contents.

Parameters:

text - the new value of the TextField, or null if the TextField is to be made empty

Throws:

java.lang.IllegalArgumentException - if text is illegal for the current input constraints

java.lang.IllegalArgumentException - if the text would exceed the current maximum capacity

See Also:

getString()

getChars

public int getChars(char[] data)

Copies the contents of the TextField into a character array starting at index zero. Array elements beyond the characters copied are left unchanged.

Parameters:

data - the character array to receive the value

Returns:

the number of characters copied

Throws:

java.lang.ArrayIndexOutOfBoundsException - if the array is too short for the contents

java.lang.NullPointerException - if data is null

See Also:

setChars(char[], int, int)

setChars

public void setChars(char[] data,
                     int offset,
                     int length)

Sets the contents of the TextField from a character array, replacing the previous contents. Characters are copied from the region of the data array starting at array index offset and running for length characters. If the data array is null, the TextField is set to be empty and the other parameters are ignored.

The offset and length parameters must specify a valid range of characters within the character array data. The offset parameter must be within the range [0..(data.length)], inclusive. The length parameter must be a non-negative integer such that (offset + length) <= data.length.

Parameters:

data - the source of the character data

offset - the beginning of the region of characters to copy

length - the number of characters to copy

Throws:

java.lang.ArrayIndexOutOfBoundsException - if offset and length do not specify a valid range within the data array

java.lang.IllegalArgumentException - if data is illegal for the current input constraints

java.lang.IllegalArgumentException - if the text would exceed the current maximum capacity

See Also:

getChars(char[])

insert

public void insert(java.lang.String src,
                   int position)

Inserts a string into the contents of the TextField. The string is inserted just prior to the character indicated by the position parameter, where zero specifies the first character of the contents of the TextField. If position is less than or equal to zero, the insertion occurs at the beginning of the contents, thus effecting a prepend operation. If position is greater than or equal to the current size of the contents, the insertion occurs immediately after the end of the contents, thus effecting an append operation. For example, text.insert(s, text.size()) always appends the string s to the current contents.

The current size of the contents is increased by the number of inserted characters. The resulting string must fit within the current maximum capacity.

If the application needs to simulate typing of characters it can determining the location of the current insertion point ("caret") using the with getCaretPosition() method. For example, text.insert(s, text.getCaretPosition()) inserts the string s at the current caret position.

Parameters:

src - the String to be inserted

position - the position at which insertion is to occur

Throws:

java.lang.IllegalArgumentException - if the resulting contents would be illegal for the current input constraints

java.lang.IllegalArgumentException - if the insertion would exceed the current maximum capacity

java.lang.NullPointerException - if src is null

insert

public void insert(char[] data,
                   int offset,
                   int length,
                   int position)

Inserts a subrange of an array of characters into the contents of the TextField. The offset and length parameters indicate the subrange of the data array to be used for insertion. Behavior is otherwise identical to insert(String, int).

The offset and length parameters must specify a valid range of characters within the character array data. The offset parameter must be within the range [0..(data.length)], inclusive. The length parameter must be a non-negative integer such that (offset + length) <= data.length.

Parameters:

data - the source of the character data

offset - the beginning of the region of characters to copy

length - the number of characters to copy

position - the position at which insertion is to occur

Throws:

java.lang.ArrayIndexOutOfBoundsException - if offset and length do not specify a valid range within the data array

java.lang.IllegalArgumentException - if the resulting contents would be illegal for the current input constraints

java.lang.IllegalArgumentException - if the insertion would exceed the current maximum capacity

java.lang.NullPointerException - if data is null

delete

public void delete(int offset,
                   int length)

Deletes characters from the TextField.

The offset and length parameters must specify a valid range of characters within the contents of the TextField. The offset parameter must be within the range [0..(size())], inclusive. The length parameter must be a non-negative integer such that (offset + length) <= size().

Parameters:

offset - the beginning of the region to be deleted

length - the number of characters to be deleted

Throws:

java.lang.IllegalArgumentException - if the resulting contents would be illegal for the current input constraints

java.lang.StringIndexOutOfBoundsException - if offset and length do not specify a valid range within the contents of the TextField

getMaxSize

public int getMaxSize()

Returns the maximum size (number of characters) that can be stored in this TextField.

Returns:

the maximum size in characters

See Also:

setMaxSize(int)

setMaxSize

public int setMaxSize(int maxSize)

Sets the maximum size (number of characters) that can be contained in this TextField. If the current contents of the TextField are larger than maxSize, the contents are truncated to fit.

Parameters:

maxSize - the new maximum size

Returns:

assigned maximum capacity - may be smaller than requested.

Throws:

java.lang.IllegalArgumentException - if maxSize is zero or less.

java.lang.IllegalArgumentException - if the contents after truncation would be illegal for the current input constraints

See Also:

getMaxSize()

size

public int size()

Gets the number of characters that are currently stored in this TextField.

Returns:

number of characters in the TextField

getCaretPosition

public int getCaretPosition()

Gets the current input position. For some UIs this may block and ask the user for the intended caret position, and on other UIs this may simply return the current caret position.

Returns:

the current caret position, 0 if at the beginning

setConstraints

public void setConstraints(int constraints)

Sets the input constraints of the TextField. If the current contents of the TextField do not match the new constraints, the contents are set to empty.

Parameters:

constraints - see input constraints

Throws:

java.lang.IllegalArgumentException - if constraints is not any of the ones specified in input constraints

See Also:

getConstraints()

getConstraints

public int getConstraints()

Gets the current input constraints of the TextField.

Returns:

the current constraints value (see input constraints)

See Also:

setConstraints(int)

setInitialInputMode

public void setInitialInputMode(java.lang.String characterSubset)

Sets a hint to the implementation as to the input mode that should be used when the user initiates editing of this TextField. The characterSubset parameter names a subset of Unicode characters that is used by the implementation to choose an initial input mode. If null is passed, the implementation should choose a default input mode.

See Input Modes for a full explanation of input modes.

Parameters:

characterSubset - a string naming a Unicode character subset, or null

Since:

MIDP 2.0

setCaret

public void setCaret(int index)

Sets the index of the caret. The caret can be used to indicate a position in the text.

Parameters:

index - the character index before which to place the caret; -1 if the caret is not displayed.

Since:

MIDP 3.0

setHighlight

public void setHighlight(int index,
                         int length)

Sets the highlight on a range in the text.

Parameters:

index - the index of the first character to be highlighted.

length - the length in characters to be highlighted.

Since:

MIDP 3.0